MySQL-SQL基础-查询2

Posted 2021-02-02 裸奔的小鸵鸟

mysql> create table customer(mid char(5) primary key,th date,sex char(1) default ‘0‘);
Query OK, 0 rows affected (0.01 sec)
mysql> desc customer;
+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| mid   | char(5)     | NO   | PRI | NULL    |       |
| name  | varchar(20) | YES  |     | NULL    |       |
| birth | date        | YES  |     | NULL    |       |
| sex   | char(1)     | YES  |     | 0       |       |
+-------+-------------+------+-----+---------+-------+
4 rows in set (0.01 sec)

mysql> insert into customer values(‘N0001‘,‘xiaoxiao‘,‘1980-11-23‘,1);
Query OK, 1 row affected (0.00 sec)

mysql> insert into customer values(‘N0002‘,‘bobo‘,‘1981-12-21‘,0);
Query OK, 1 row affected (0.00 sec)

mysql> create table goods(id int auto_increment primary key,name varchar(30));
Query OK, 0 rows affected (0.01 sec)

mysql> insert into goods values(1,‘taotao‘);
Query OK, 1 row affected (0.01 sec)

mysql> insert into goods values(2,‘meimei‘);
Query OK, 1 row affected (0.00 sec)

mysql> select * from goods;
+----+--------+
| id | name   |
+----+--------+
|  1 | taotao |
|  2 | meimei |
+----+--------+
2 rows in set (0.00 sec)

mysql> select * from customer;
+-------+----------+------------+------+
| mid   | name     | birth      | sex  |
+-------+----------+------------+------+
| N0001 | xiaoxiao | 1980-11-23 | 1    |
| N0002 | bobo     | 1981-12-21 | 0    |
+-------+----------+------------+------+
2 rows in set (0.00 sec)

mysql> insert into customer values(‘G0001‘,‘dudu‘,‘1975-04-18‘,0);
Query OK, 1 row affected (0.00 sec)

mysql> insert into customer values(‘G0002‘,‘yuyu‘,‘1985-04-20‘,1);
Query OK, 1 row affected (0.00 sec)

mysql> select * from customer;
+-------+----------+------------+------+
| mid   | name     | birth      | sex  |
+-------+----------+------------+------+
| G0001 | dudu     | 1975-04-18 | 0    |
| G0002 | yuyu     | 1985-04-20 | 1    |
| N0001 | xiaoxiao | 1980-11-23 | 1    |
| N0002 | bobo     | 1981-12-21 | 0    |
+-------+----------+------------+------+
4 rows in set (0.00 sec)

mysql> select * from goods;
+----+--------+
| id | name   |
+----+--------+
|  1 | taotao |
|  2 | meimei |
+----+--------+
2 rows in set (0.00 sec)

mysql> select * from customer where birth=NULL;
Empty set (0.00 sec)

mysql> select name,birth,sex from customer where sex=‘1‘ and birth is not null;
+----------+------------+------+
| name     | birth      | sex  |
+----------+------------+------+
| yuyu     | 1985-04-20 | 1    |
| xiaoxiao | 1980-11-23 | 1    |
+----------+------------+------+
2 rows in set (0.00 sec)

mysql> select name,birth,sex from customer where birth<=‘1976-01-01‘ or birth>=‘1980-01-01‘ and sex=‘1‘;
+----------+------------+------+
| name     | birth      | sex  |
+----------+------------+------+
| dudu     | 1975-04-18 | 0    |
| yuyu     | 1985-04-20 | 1    |
| xiaoxiao | 1980-11-23 | 1    |
+----------+------------+------+
3 rows in set (0.00 sec)

mysql> select name,birth,sex from customer where (birth<=‘1976-01-01‘ or birth>=‘1980-01-01‘) and sex=‘1‘;
+----------+------------+------+
| name     | birth      | sex  |
+----------+------------+------+
| yuyu     | 1985-04-20 | 1    |
| xiaoxiao | 1980-11-23 | 1    |
+----------+------------+------+
2 rows in set (0.01 sec)

mysql> select name,birth,sex from customer order by sex asc,birth desc;
+----------+------------+------+
| name     | birth      | sex  |
+----------+------------+------+
| bobo     | 1981-12-21 | 0    |
| dudu     | 1975-04-18 | 0    |
| yuyu     | 1985-04-20 | 1    |
| xiaoxiao | 1980-11-23 | 1    |
+----------+------------+------+
4 rows in set (0.00 sec)